Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011
Cash Provided by (Used in) Operating Activities:
Net Income	$ 5,199	$ 4,424
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation	2,655	2,712
Amortization	370	340
Amortization of deferred gain	(261)	(261)
Provision for bad debts	(253)	(2)
Provision for accrued warranty costs	133	4
Warranty costs paid	(138)	(140)
Stock-based compensation and directors' fees	727	1,043
Excess tax benefit from stock-based awards	(596)	(612)
Unrealized (gain) loss on short-term investments	(1)	5
Unrealized loss (gain) on foreign exchange contracts	106	221
Unrealized foreign currency transaction gain	(47)	(186)
Changes in operating assets and liabilities:
Accounts receivable	(2,737)	(97)
Inventories	(3,807)	(10,241)
Other assets	460	(1,522)
Accounts payable	2,300	2,280
Other liabilities	(1,936)	(3,299)
Net Cash Provided by (Used in) Operating Activities	2,174	(5,331)
Cash Used in Investing Activities:
Purchases of short-term investments	(12,678)	(10,010)
Sales of short-term investments	12,580	11,915
Additions to property, plant and equipment	(1,844)	(1,851)
Additions to trademarks and patents	(166)	(91)
Net Cash Used in Investing Activities	(2,108)	(37)
Cash (Used in) Provided by Financing Activities:
Borrowing on long-term debt	3,000	11,000
Repayment of long-term debt	(6,000)	(9,000)
Excess tax benefit from stock-based awards	597	612
Proceeds from sale of Class A common stock, net	317	(118)
Purchase of treasury stock	(1,502)	(1,132)
Net Cash (Used in) Provided by Financing Activities	(3,588)	1,362
Effect of exchange rate changes on cash and cash equivalents	146	131
Decrease in Cash and Cash Equivalents	(3,376)	(3,875)
Cash and cash equivalents at beginning of period	25,991	16,650
Cash and Cash Equivalents at End of Period	22,615	12,775
SUPPLEMENTAL INFORMATION
Income taxes paid, net	630	453
Interest paid	$ 237	$ 370